The objective of this project is to create a publicly available electronic neuroanatomy resource that will advance neuroscience research and spread neuroanatomical knowledge. We will label all neuroanatomical regions in a large number of publicly available MRI brain scans. Using semi- automatic software, technicians with extensive training will apply precisely defined measurement methods to make outlines around regions so that the entire brain is identified in every scan. We will then combine all of these results into a new kind of computerized atlas that can be used to 1) locate and identify brain regions in other scans, and 2) to interactively learn brain anatomy. We will make all of our results available to the public. Releasing this large-scale atlas will address a critical barrier to progress in the field of structural brain analysis by providing a "gold standard". This will enable the development of highly accurate automatic brain measurement systems. After a patient gets a MRI brain scan, these systems will provide numbers indicating the size of each brain region. For example, the hippocampus is a brain region involved in memory that shrinks in Alzheimer's disease. These numbers can be used for diagnosis and to guide treatment for a wide range of brain disorders. PUBLIC HEALTH RELEVANCE: The proposed project will help in the understanding of how the structure of the brain changes in response to neurological and psychiatric disorders. Knowing precisely where, how and how much the shape of the brain changes will improve public health because it is quantitative information that goes beyond the qualitative analysis that is currently performed in radiology today.